West Marine Air Dryer Repair - FWIW


Well-Known Member
Jan 31, 2005
My air dryer stopped working last year after about 2+ years of operation. I finally got around to investigating and fixing it.
110vac comes into the unit and basically goes to three functions: red led to indicate power, round heating element on the circumference of the unit and a small fan that is in the center.
You can quickly determine what is the issue using a DVM and/or some substitution logic. Take pictures if you need to.

- Fuse. Measure across the thermal fuse with a DVM. It should be shorted. In my case it was open. I simply jumped the fuse to allow power to flow to the three functions. Everything worked fine. I ended up ordering a new fuse and installing. You can get it at Amazon or DigiKey (THERMAL CUTOFF FUSE 91 Degrees Celsius 10A by 250V). Suggest you install with spade crimped connectors for easy removal and jumping in the future. Shrink tube and tie wrap as done when manufactured to ensure the wires don't contact the fan blades.
- Fan, led and Heater. If the fuse is not the issue you can unplug each of these at a time an isolate what is bad or use a DVM and measure them. Suggest you jumper the fuse so you are not continually blowing it. I didn't need to change or check these items in my case as everything worked. I'm sure there are part numbers on them that could be cross referenced on the net (as done with the fuse) and you can find them. I think the led is a non issue, it should be on when plugged in and off when unplugged.

In my case I'm not sure what caused the device to open. I'm going to run the unit for a couple of days in the workshop and see if anything occurs over time. Looks like it will run fine and go back in the cabin in the spring.

Other than the reliability issue (there have been other folks that have had failures) these things work pretty well. Perfect for a GW cabin from a square footage perspective. My cabin was always dry and never had any mold issues. The heater is equivalent to a 40w light bulb from a heat perspective, just enough to address the mold concern. The fan circulates the air nicely and is quiet.

Link to item: https://www.westmarine.com/buy/west...an-dehumidifier-120v-ac--7867518?recordNum=14